844 resultados para Aalberg, Ida,


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The present paper deals with experimentation of ZrO2 and Al2O3-supported catalysts for conversion of naphthalene, chosen as tar model compound of pyrolysis or gasification syngas. In particular, the reforming capacity of active metals and promoters such as Co, Ni, Fe, Cr, Ce and Pt was tested in a fixed bed reactor at temperature from 400 to 900 °C. As regards ZrO2-supported catalysts, the best results were achieved by the Ni/Fe/Pt catalyst with 96% naphthalene conversion, 78% and 280% as CO and H2 production yield at 800 °C. Regarding Al2O3-supported catalysts, they were more active on average than the zirconia ones, achieving a very good performance even at 500 °C (90–100% naphthalene conversion, 30–40% CO yield and 300–350% H2 yield at 550 °C). Influence of different amounts of alumina, montmorillonite and carbon on carrier composition as well as pellets’ size were also studied. Both zirconia and alumina catalysts showed deactivation at higher temperatures due to coke deposition, resulting in a strong H2 production drop. Regeneration of catalysts by O2 and steam as well as activation by H2 were also studied. The activated catalyst was able to convert more than 99% naphthalene at 450 °C with a CO and H2 production yield of 26% and 420%, respectively.

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Vesicular adjuvant systems composing dimethyldioctadecylammonium (DDA) can promote both cell-mediated and humoral immune responses to the tuberculosis vaccine fusion protein in mice. However, these DDA preparations were found to be physically unstable, forming aggregates under ambient storage conditions. Therefore there is a need to improve the stability of such systems without undermining their potent adjuvanticity. To this end, the effect of incorporating non-ionic surfactants, such as 1-monopalmitoyl glycerol (MP), in addition to cholesterol (Chol) and trehalose 6,6′-dibehenate (TDB), on the stability and efficacy of these vaccine delivery systems was investigated. Differential scanning calorimetry revealed a reduction in the phase transition temperature (T c) of DDA-based vesicles by ∼12°C when MP and cholesterol (1:1 molar ratio) were incorporated into the DDA system. Transmission electron microscopy (TEM) revealed the addition of MP to DDA vesicles resulted in the formation of multi-lamellar vesicles. Environmental scanning electron microscopy (ESEM) of MP-Chol-DDA-TDB (16:16:4:0.5 μmol) indicated that incorporation of antigen led to increased stability of the vesicles, perhaps as a result of the antigen embedding within the vesicle bilayers. At 4°C DDA liposomes showed significant vesicle aggregation after 28 days, although addition of MP-Chol or TDB was shown to inhibit this instability. Alternatively, at 25°C only the MP-based systems retained their original size. The presence of MP within the vesicle formulation was also shown to promote a sustained release of antigen in-vitro. The adjuvant activity of various systems was tested in mice against three subunit antigens, including mycobacterial fusion protein Ag85b-ESAT-6, and two malarial antigens (Merozoite surface protein 1, MSP1, and the glutamate rich protein, GLURP). The MP- and DDA-based systems induced antibody responses at comparable levels whereas the DDA-based systems induced more powerful cell-mediated immune responses. © 2006 The Authors.

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Incorporation of the glycolipid trehalose 6,6′-dibehenate (TDB) into cationic liposomes composed of the quaternary ammonium compound dimethyldioctadecylammonium (DDA) produce an adjuvant system which induces a powerful cell-mediated immune response and a strong antibody response, desirable for a high number of disease targets. We have used differential scanning calorimetry (DSC) to investigate the effect of TDB on the gel-fluid phase transition of DDA liposomes and to demonstrate that TDB is incorporated into DDA liposome bilayers. Transmission Electron Microscopy (TEM) and cryo-TEM confirmed that liposomes were formed when a lipid film of DDA containing small amounts of TDB was hydrated in an aqueous buffer solution at physiological pH. Furthermore, time development of particle size and zeta potential of DDA liposomes incorporating TDB during storage at 4°C and 25°C, indicates that TDB effectively stabilizes the DDA liposomes. Immunization of mice with the mycobacterial fusion protein Ag85B-ESAT-6 in DDA-TDB liposomes induced a strong, specific Th1 type immune response characterized by substantial production of the interferon-γ cytokine and high levels of IgG2b isotype antibodies. The lymphocyte subset releasing the interferon-γ was identified as CD4 T cells.

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Conventional methods in horizontal drilling processes incorporate magnetic surveying techniques for determining the position and orientation of the bottom-hole assembly (BHA). Such means result in an increased weight of the drilling assembly, higher cost due to the use of non-magnetic collars necessary for the shielding of the magnetometers, and significant errors in the position of the drilling bit. A fiber-optic gyroscope (FOG) based inertial navigation system (INS) has been proposed as an alternative to magnetometer -based downhole surveying. The utilizing of a tactical-grade FOG based surveying system in the harsh downhole environment has been shown to be theoretically feasible, yielding a significant BHA position error reduction (less than 100m over a 2-h experiment). To limit the growing errors of the INS, an in-drilling alignment (IDA) method for the INS has been proposed. This article aims at describing a simple, pneumatics-based design of the IDA apparatus and its implementation downhole. A mathematical model of the setup is developed and tested with Bloodshed Dev-C++. The simulations demonstrate a simple, low cost and feasible IDA apparatus.

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The Church of Our Blessed Redeemer Who Walked Upon the Waters is a collection of short stories about Elwyn Parker, a devout pianist who becomes a worldly car salesman. "Thirty Fingers," "My Father's Business," and "Apostate" introduce Elwyn, a saint at church and a trouble-making evangelist at school, who nevertheless finds himself in a love affair with an older woman, Sister Morrisohn. In "Captivity," Elwyn, a college freshman, experiences worldliness, then grows to resent and ultimately reject Sister Morrisohn. In "The Leap," Elwyn is back at the piano, but unemployed and unhappily married. He finds comfort only in his decade-old affair. In "The Lord of Travel," Elwyn, a car salesman, appears bereft of his former morals until he hoodwinks Ida, who reminds him of the now deceased Sister Morrisohn. Elwyn repairs Ida's car, redeeming himself in the process.

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From inquiries concerning the child as an individual with rights, this work takes as its object of study the perception of 5-7 years old children on their journey from kindergarten to elementary school, in a school culture. The objective of the research is, therefore, to investigate what the children tell in narratives drawn into a conversation circle about their experiences of school life in kindergarten and the first grade of elementary school. The participants were 18 children from a public school in the city of Natal (RN). Five rounds of conversation were held in which the children told a little alien, who was unaware of the school culture, what they knew about school and what they did at it. The research is linked to the project "Children's Narratives. What the children tell about childhood schools?"(Passeggi et all, 2011) and adopts epistemological principles and research methods of (auto)biographical education, taking as a working hypothesis the child's ability to reflect on their experiences and understand from their point of view, what happens to them. Analyses were organized based on the concept of school culture (Barroso, 2012). In the narratives of children, the three dimensions of school culture: the functionalist (purpose and rules), structural (structure and pedagogical organization) and the interactional (relations with others, with the spaces and with knowledge) are considered intertwined in their school perceptions and signal experienced tensions in a process of "conversion" from child to student. Children seem to realize the uniqueness of each level of education. They recognize as a characteristic of early childhood education the recreational activities, and as injunctions of the first year of elementary school the "study", "learning to read and write" to "be smart" to "change." The schooling will thus, constitute, in their eyes, as a time and a place where the children's culture gives way to school culture, and in this journey they experience that the desire to play and the duty/want to study cross the three dimensions of school. At the end of the journey, the status of children as cultural beings with rights is confirmed, whose narratives about school and about their experiences of "conversion" in a student, reveal much about the power of reflection on themselves, the school and the society in which they live, legitimizing their place in educational research and in child care policies.

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Surveying habitats critical to the survival of grey nurse sharks in South-East Queensland has mapped critical habitats, gathered species inventories and developed protocols for ecological monitoring of critical habitats in southern Queensland. This information has assisted stakeholders with habitat definition and effective management. In 2002 members of UniDive applied successfully for World Wide Fund for Nature, Threatened Species Network funds to map the critical Grey Nurse Shark Habitats in south east Queensland. UniDive members used the funding to survey, from the boats of local dive operators, Wolf Rock at Double Island Point, Gotham, Cherub's Cave, Henderson's Rock and China Wall at North Moreton and Flat Rock at Point Look Out during 2002 and 2003. These sites are situated along the south east Queensland coast and are known to be key Grey Nurse Shark aggregation sites. During the project UniDive members were trained in mapping and survey techniques that include identification of fish, invertebrates and substrate types. Training was conducted by experts from the University of Queensland (Centre of Marine Studies, Biophysical Remote Sensing) and the Queensland Parks and Wildlife Service who are also UniDive members. The monitoring methods (see methods) are based upon results of the UniDive Coastcare project from 2002, the international established Reef Check program and research conducted by Biophysical Remote Sensing and the Centre of Marine Studies. Habitats were mapped using a combination of towed GPS photo transects, aerial photography, bathymetry surveys and expert knowledge. This data provides georeferenced information regarding the major features of each of Sites mapped including Wolf Rock

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El cartel serigráfico del proyecto de carteles del Taller de Cinema y Gráfica de Parques y Recreo Público se utilizó como medio para educar e insertar a las grandes masas dentro de las reformas coloniales ocurridas como consecuencia de la entrada de Estados Unidos a la Segunda Guerra Mundial y readiestrar a la población puertorriqueña, entonces compuesta por campesinos, para servir como mano de obra barata y dócil al proyecto colonial y a los beneficiarios del proyecto de industrialización de la posguerra. Se ha dicho en innumerables ocasiones que el camino al infierno está repleto de buenas intenciones; este es el relato de un viaje de ida. Los carteles de la División de Cinema y Gráfica de Parques y Recreo Público mantienen desde el origen varios elementos inquietantes de lo que se podría denominar como la política de reconstrucción de una colonia, de un territorio objeto de la sujeción/subyugación por parte de otro país, y presentarlo como un objetivo plausible, de consideración y cumplimiento con los derechos humanos fundamentales...

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The purpose of this study is to examine the effects of agglomeration economies on the productivity of manufacturing local units in Ireland. Four types of agglomeration economies are considered in this study. These are internal economies of scale, localization economies, related variety and urbanization economies. This study makes a number of contributions to the literature. Firstly, this is the first study to conduct an investigation of the effects of agglomeration economies on the productivity of manufacturing local units operating in Ireland. Secondly, this study distinguishes between indigenous and foreign-owned local units which is important given the dual nature of the Irish economy (Krugman, 1997). Thirdly, in addition to considering the effects of agglomeration economies, this study examines the impact of spurious agglomeration on the productivity of foreign-owned local units. Using data from the Census of Industrial Local Units and a series of IV GMM estimators to control for endogeneity, the results of the analysis conducted in Chapter 6 reveal that there are differences in the effects of agglomeration economies on the productivity of indigenous and foreign-owned local units. In Chapter 7 the Census of Industrial Local Units is supplemented by additional data sources and more in-depth measures are generated to capture the features of each of the external agglomeration economies considered in this analysis. There is some evidence to suggest that the availability of local inputs has a negative and significant impact on productivity. The NACE based measures of related variety reveal that the availability of local inputs and knowledge spillovers for related sectors have a negative and significant impact on productivity. There is clear evidence to suggest that urbanization economies are important for increasing the productivity of indigenous local units. The findings reveal that a 1% increase in population density in the NUTS 3 region leads to an increase in the productivity of indigenous local units of approximately 0.07% to 0.08%. The results also reveal that there is a significant difference in the effects of agglomeration economies on the productivity of low-tech and medium/high-tech indigenous local units. The more in-depth measures of agglomeration economies used in Chapter 7 are also used in Chapter 8. A series of IV GMM regressions are estimated in order to identify the impact of agglomeration economies and spurious agglomeration on the productivity of foreign-owned local units operating in Ireland. There is some evidence found to suggest that the availability of a pool of skilled labour has a positive and significant on productivity of foreign-owned local units. There is also evidence to suggest that localization knowledge spillovers have a negative impact on the productivity of foreign-owned local units. There is strong evidence to suggest that the availability of local inputs has a negative impact on the productivity. The negative impact is not confined to the NACE 4-digit sector but also extends into related sectors as determined by Porter’s (2003) cluster classification. The cluster based skills measure of related variety has a positive and significant impact on the productivity of foreign-owned local units. Similar to Chapter 7, there is clear evidence to suggest that urbanization economies are important for increasing the productivity of foreign-owned local units. Both the summary measure and each of the more in-depth measures of agglomeration economies have a positive and significant impact on productivity. Spurious agglomeration has a positive and significant impact on the productivity of foreign-owned local units. The results indicate that the more foreign-owned local units of the same nationality in the country the greater the levels of productivity for the local unit. From a policy perspective, urbanization economies are clearly important for increasing the productivity of both indigenous and foreign-owned local units. Furthermore, the availability of a pool of skilled labour appears to be important for increasing the productivity of foreign-owned local units. Another policy implication that arises from these results relates to the differences observed between indigenous local units and foreign-owned local units and also between low-tech and medium/high-tech indigenous local units. These findings indicate that ‘one-size-fits-all’ type policies are not appropriate for increasing the productivity of local units operating in Ireland. Policies should be tailored to the needs of either indigenous or foreign-owned local units and also to specific sectors. This positive finding for own country spurious agglomeration is important from a policy perspective and is one that IDA Ireland should take on board.

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Ruy González de Clavijo protagonizó, junto con un equipo de negociadores, la segunda embajada que enviara Enrique III de Castilla a Tamorlán en 1403, cuyo itinerario de ida y vuelta se extiendepor tres años. El autor publica un relato de viaje que compendia una relación de hechos y una descripción minuciosa de la geografía de lastierras transitadas, poblaciones visitadas y las costumbres de los lugareños hasta llegar a Samarcanda, capital del imperio tártaro. El relato de Clavijo brinda unfuerte componente informativo y documental, con la inmediatez y la frescura del testimonio de los viajeros que presencian directamente la mayoría de los acontecimientos por ellos relatados y transmiten sus experiencias concretas. El objetivo de este trabajo es describir las características que los viajeros refieren a lo largo de su periplo, en dos aspectos fundamentales: el aspecto físico de los individuos y la relación que establecen con el espacio natural. En primer término abordaremos la descripción del otro lejano, sus características peculiares, las vestimentas, las costumbres alimentarias, los alojamientos y mobiliario. Seguidamente sintetizaremos los ambientes naturales descriptos por los viajeros: una geografía que se señala como adversa a los desplazamientos prolongados. El autor muestra un interés especial por la transformación de la naturaleza en función de la producción de alimentos y la comercialización de los mismos, así como el tratamiento eficiente de los recursos naturales que facilitan el traslado y la habitabilidad. La hipótesis general sería que la alteridad se percibe en relación a la propia experiencia cultural, y es así como las descripciones de los individuos, las comunidades y el entorno natural se piensan y se traducen en relación con las representaciones del sujeto itinerante. La hipótesis secundaria es que las descripciones se ajustan a las exigencias de la embajada, a las necesidades de concretar las metas de alianza política y económica con el líder tártaro.

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El presente texto analiza la función del Instituto de Investigaciones y Experiencias Cinematográficas (IIEC) como punto de encuentro de la cultura cinematográfica nacional entre 1947 y 1955 —los años de Victoriano López— y dirige el foco analítico a los discursos, debates e intereses que marcaron la labor del instituto en estos primeros años. Para ello, este artículo fija su atención en uno de los pocos docu­mentos originales conservados de esa época, un boletín publicado por los alumnos en 1951, material que será aquí completado con entrevistas y los escasos documentos referentes al instituto conservados en el Archivo General de la Administración. La piedra de toque del análisis la constituyen por un lado las ac­tividades del cineclub, organizado por los alumnos de la clase de Historia del Cine en 1951, y, en el plano discursivo, los debates en torno a la Filmología, doctrina con la que desde 1947 se intenta dotar a las acti­vidades del Instituto de una base teórica con desiguales resultados. Se consigue así un acercamiento a las prácticas y discursos esenciales para comprender la importancia del instituto como punto central dentro de una naciente cultura cinematográfica nacional.

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International migration sets in motion a range of significant transnational processes that connect countries and people. How migration interacts with development and how policies might promote and enhance such interactions have, since the turn of the millennium, gained attention on the international agenda. The recognition that transnational practices connect migrants and their families across sending and receiving societies forms part of this debate. The ways in which policy debate employs and understands transnational family ties nevertheless remain underexplored. This article sets out to discern the understandings of the family in two (often intermingled) debates concerned with transnational interactions: The largely state and policydriven discourse on the potential benefits of migration on economic development, and the largely academic transnational family literature focusing on issues of care and the micro-politics of gender and generation. Emphasizing the relation between diverse migration-development dynamics and specific family positions, we ask whether an analytical point of departure in respective transnational motherhood, fatherhood or childhood is linked to emphasizing certain outcomes. We conclude by sketching important strands of inclusions and exclusions of family matters in policy discourse and suggest ways to better integrate a transnational family perspective in global migration-development policy.

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Mallorca, the largest of the Balearic Islands, is a well-known summer holidays destination; an ideal place to relax and enjoy the sun and the sea. That tourist gaze reflected on postcards results from advertising campaigns, where cinema played an important role with documentaries and fiction films. The origins of that iconography started in the decades of the 1920’s and 1930’s, reflecting the so-called myth of the “island of calm”. On the other hand, the films of the 1950’s and 1960’s created new stereotypes related to the mass tourism boom. Busy beaches and the white bodies of tourists replaced white sandy beaches, mountains and landscapes shown up in the movies of the early decades of the 20th century. Besides, hotels and nightclubs also replaced monuments, rural landscapes and folk exhibitions. These tourist images mirror the social and spatial transformations of Mallorca, under standardization processes like other seaside mass tourist destinations. The identity was rebuilt on the foundations of "modernity". Although "balearization" has not ceased, nowadays filmmaking about Mallorca is advertising again a stereotype close to that one of the 1920s and 1930s, glorifying the myth of the "island of calm". This singular identity makes the island more profitable for capital that searches socio-spatial differentiation in post-fordist times.

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We report 3 au resolution imaging observations of the protoplanetary disk aroundTW Hya at 145 and 233 GHz with the Atacama Large Millimeter/Submillimeter Array.Our observations revealed two deep gaps (~25-50 %) at 22 and 37 au and shallowergaps (a few %) at 6, 28, and 44 au, as recently reported by Andrews et al. (2016). Thecentral hole with a radius of  3 au was also marginally resolved. The most remarkablefinding is that the spectral index α(R) between bands 4 and 6 peaks at the 22 au gap.The derived power-law index of the dust opacity β(R) is  ~1.7 at the 22 au gap anddecreases toward the disk center to ~0. The most prominent gap at 22 au could becaused by the gravitational interaction between the disk and an unseen planet with amass of ≲1.5 MNeptune although other origins may be possible. The planet-induced gap is supported by the fact that β(R) is enhanced at the 22 au gap, indicating a deficitof mm-sized grains within the gap due to dust filtration by a planet.